Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Medical Lake you should be able to estimate when you can plant pennyroyal.

Planting Calendar for Pennyroyal

Frost tolerance for pennyroyal:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Pennyroyal do well in pretty solid cold which tells us that you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant pennyroyal in Medical Lake is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant pennyroyal and expect a good harvest is probably September. You probably don't want to wait any later than that or else your pennyroyal may not have a chance to grow to maturity. Starting your pennyroyal indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Medical Lake. You can expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Medical Lake may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Medical Lake there is a last frost after April 15 be ready to protect your pennyroyal in the event of one of those late frosts.

USDA Zone Info for Medical Lake

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Medical Lake

You may be interested in your other planting guides for Medical Lake.